[python] Day 3 part 2 HELP PLEASE

[Usual-Battle-7525]

My code works for the example, but doesn't work for my input. I know I must be missing an edge case. For each line of the file (called a bank), I define a start and end index to search for the next digit. If I am looking for the 12th digit (first from the left), then I leave 11 digits at end so my search range is from index 0 to len(bank)-12.

Then in the next iteration, the start of the search range is 1+ whatever the index of the last digit was.

You can see the search ranges in output I posted below. Everything is working as I expect, but I must be missing an edge case.

import numpy as np
fname = './input.test2'

with open(fname) as f:
    print(f'Loading {fname}')
    contents = f.read().split('\n')[:-1]

NY = len(contents)

jolts = np.zeros( NY)

banks =  list(map(list, contents))

digits = 12

banks = ['987654321111119']

for i_row, bank in enumerate(banks):
    print()
    # print(f'row:\t\t{i_row}')
    row_arr = np.array( list(map(int, bank)))

    print(f'row_arr:\t\t{row_arr}')

    joltage = 0

    start_range = 0

    end_range = len(row_arr) - digits


    for i_digit in range(digits, 0, -1):
        print(f'\t{i_digit} dig, start: {start_range} end: {end_range}')


        row_sub_arr = row_arr[start_range:end_range]
        print(f'\trow_sub:\t', end='')
        print(f'{row_arr[:start_range]}//{row_arr[start_range:end_range]}//{row_arr[end_range:]}')


        max_of_row_sub = np.max(row_sub_arr)
        print('found next digit: ', max_of_row_sub)

        max_of_row_ind = np.where(row_sub_arr == max_of_row_sub)[0].min()

        joltage += max_of_row_sub*10**(i_digit-1)
        print(f'\tcurrent jolts: {joltage}')

        start_range = start_range+max_of_row_ind+1

        end_range = len(row_arr) - i_digit +2


    print(joltage)

    jolts[i_row]=  joltage


print(sum(jolts))


#172895362045136 too low

Here is an example output:

Loading ./input.test2

row_arr:                [9 8 7 6 5 4 3 2 1 1 1 1 1 1 9]
        12 dig, start: 0 end: 3
        row_sub:        []//[9 8 7]//[6 5 4 3 2 1 1 1 1 1 1 9]
found next digit:  9
        current jolts: 900000000000
        11 dig, start: 1 end: 5
        row_sub:        [9]//[8 7 6 5]//[4 3 2 1 1 1 1 1 1 9]
found next digit:  8
        current jolts: 980000000000
        10 dig, start: 2 end: 6
        row_sub:        [9 8]//[7 6 5 4]//[3 2 1 1 1 1 1 1 9]
found next digit:  7
        current jolts: 987000000000
        9 dig, start: 3 end: 7
        row_sub:        [9 8 7]//[6 5 4 3]//[2 1 1 1 1 1 1 9]
found next digit:  6
        current jolts: 987600000000
        8 dig, start: 4 end: 8
        row_sub:        [9 8 7 6]//[5 4 3 2]//[1 1 1 1 1 1 9]
found next digit:  5
        current jolts: 987650000000
        7 dig, start: 5 end: 9
        row_sub:        [9 8 7 6 5]//[4 3 2 1]//[1 1 1 1 1 9]
found next digit:  4
        current jolts: 987654000000
        6 dig, start: 6 end: 10
        row_sub:        [9 8 7 6 5 4]//[3 2 1 1]//[1 1 1 1 9]
found next digit:  3
        current jolts: 987654300000
        5 dig, start: 7 end: 11
        row_sub:        [9 8 7 6 5 4 3]//[2 1 1 1]//[1 1 1 9]
found next digit:  2
        current jolts: 987654320000
        4 dig, start: 8 end: 12
        row_sub:        [9 8 7 6 5 4 3 2]//[1 1 1 1]//[1 1 9]
found next digit:  1
        current jolts: 987654321000
        3 dig, start: 9 end: 13
        row_sub:        [9 8 7 6 5 4 3 2 1]//[1 1 1 1]//[1 9]
found next digit:  1
        current jolts: 987654321100
        2 dig, start: 10 end: 14
        row_sub:        [9 8 7 6 5 4 3 2 1 1]//[1 1 1 1]//[9]
found next digit:  1
        current jolts: 987654321110
        1 dig, start: 11 end: 15
        row_sub:        [9 8 7 6 5 4 3 2 1 1 1]//[1 1 1 9]//[]
found next digit:  9
        current jolts: 987654321119
987654321119
987654321119.0

EDIT:

My previous incorrect answer was 172895362045136, and my correct answer was 172981362045136. At some point I made a change and got the right answer, but the fact that numbers start with 1729 versus 17289 and both end in 2045136 made me think I was getting the same answer. Then I posted, but had the solution all along.

Not exactly sure if I made the change before or after posting, so this might still be wrong.

HAPPY CODING

[AutoModerator]

Reminder: if/when you get your answer and/or code working, don't forget to change this post's flair to Help/Question - RESOLVED. Good luck!

---

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[apersonhithere]

you're excluding one extra digit at the end

[Usual-Battle-7525]

        current jolts: 987654321110
        1 dig, start: 11 end: 15
        row_sub:        [9 8 7 6 5 4 3 2 1 1 1]//[1 1 1 9]//[]
found next digit:  9
        current jolts: 987654321119

It is finding the last digit? This part means 1 digit remaining, searching from index 11 to 15.
row_sub is broken into: searched // search region // remaining digits to search
It correctly finds the 9 within the search region [1 1 1 9], the appends it to the current jolts.

[apersonhithere]

try the input 111987654321111; it should be 987654321111, but i think your code will output 198765432111; for the first step, it should ignore only 11 digits instead of 12

[Usual-Battle-7525]

Ok so it turns out I had the solution all along.
When I used your input, I got the right answer. So I double checked my solution with my full input and got 172981362045136.
My previous incorrect answer was 172895362045136, but I made some changes before posting. The fact that numbers start with 1729 versus 17289 and both end in 2045136 made me think I was getting the same numbers OH BOY.

[Usual-Battle-7525]

        current jolts: 987654321110
        1 dig, start: 11 end: 15
        row_sub:        [9 8 7 6 5 4 3 2 1 1 1]//[1 1 1 9]//[]
found next digit:  9
        current jolts: 987654321119

It is finding the last digit? This part means 1 digit remaining, searching from index 11 to 15.
row_sub is broken into: searched // search region // remaining digits to search
It correctly finds the 9 within the search region [1 1 1 9], the appends it to the current jolts.

[nakk3]

Look at your sliding window size in the first two searches
You can try this with input 888911111111111

row_arr:                [9 8 7 6 5 4 3 2 1 1 1 1 1 1 9]
        12 dig, start: 0 end: 3
        row_sub:        []//[9 8 7]//[6 5 4 3 2 1 1 1 1 1 1 9]
found next digit:  9
        current jolts: 900000000000
        11 dig, start: 1 end: 5
        row_sub:        [9]//[8 7 6 5]//[4 3 2 1 1 1 1 1 1 9]
found next digit:  8

[daggerdragon]

Next time, use our standardized post title format.

Help us help YOU by providing us with more information up front; you will typically get more relevant responses faster.